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26782. The influence of hormonal changes during menstrual cycle on serum adiponectin concentrations in healthy women
- Creator:
- Kleiblová, P., Springer, D., and Haluzík , M.
- Type:
- article, model:article, and TEXT
- Subject:
- Adiponectin, Menstrual cycle, Cortisol, and Insulin sensitivity
- Language:
- English
- Description:
- Adiponectin is an adipocyte-derived hormone involved in the regulation of carbohydrate and lipid metabolism. Its concentrations are decreased in patients with obesity, type 2 diabetes and atherosclerosis and are higher in females than in males. Gender differences of adiponectin levels raise the possibility that sex hormones directly regulate its serum concentrations, which may in turn influence insulin sensitivity in different phases of the menstrual cycle. To test this hypothesis we measured serum adiponectin, estradiol, progesterone, luteinizing hormone and follicle-stimulating hormone concentrations daily throughout the menstrual cycle in six healthy women. Mean adiponectin levels strongly positively correlated with serum cortisol concentrations [R=0.94286; p=0.0048 (Spearman correlation test)], but were not significantly related to other anthropometric, biochemical and hormonal characteristics of the subjects (BMI, blood glucose, insulin, testosterone, prolactin, cholesterol, HDL cholesterol, LDL cholesterol, triglycerides concentrations, or atherogenic index). Furthermore, no significant changes of serum adiponectin levels were found throughout the menstrual cycle. We conclude that changes in sex hormones during the menstrual cycle do not affect total circulating adiponectin levels in healthy women. Therefore, the differences in insulin sensitivity in various phases of the menstrual cycle are not due to changes of circulating adiponectin levels.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
26783. The influence of insulin on the in vitro development of mouse and bovine embryos
- Creator:
- Mihalik, J., Rehák, P., and Juraj Koppel
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, inzulin, insulin, preimplantation embryo, mouse, bovine, development, 14, and 612
- Language:
- English
- Description:
- To further investigate the role of insulin during preimplantation embryo development, we compared the effects of insulin on the development of mouse and bovine preimplantation embryos and on cell proliferation during culture in vitro in simplex media. The influence of insulin on the development of mouse zygotes was determined during cultivation in mSOF medium, alone or supplemented with glucose. Similarly, the effects of insulin on the bovine preimplantation embryo development were studied in mSOF medium. The addition of insulin into mSOF medium enhanced significantly the number of cells per mouse blastocyst. Moreover, when mSOF medium was supplemented with insulin and 0.2 mmol.l-1 glucose, the percentage of hatched blastocysts and the mean cell number of mouse blastocysts were significantly higher. Insulin had no significant effect on the development of bovine embryos, produced by in vitro fertilization of in vitro matured oocytes. Neither the rates of developing embryos nor the mean number of cells in blastocysts were different in comparison with control embryos. Our results suggest that the in vitro development of mouse embryos could be enhanced by the addition of insulin to the culture medium and is further improved by the addition of glucose. In contrast to this our results indicate that insulin has no detectable beneficial effect on the preimplantation development of bovine embryos in mSOF medium., J. Mihalik, P. Rehák, J. Koppel., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
26784. The influence of interleukin-1β on γ-glutamyl transpepidase activity in rat hippocampus
- Creator:
- Kiaser, M., Mareš, V., Šťastný , F., Bubeníková-Valešová, V., Lisá, V., Suchomel, P., and Balcar, V.J.
- Type:
- article, model:article, and TEXT
- Subject:
- Pro-inflammatory cytokine, Rat hippocampus, γ-glutamyl transferase, Blood-brain barrier, Reactive oxygen species, and Schizophrenia
- Language:
- English
- Description:
- Brain infections as well as peripheral challenges to the immune system lead to an increased production of interleukin-1beta (IL-1b), a cytokine involved in leukocyte-mediated breakdown of the blood-brain barrier. The effects of IL-1b have been reported to depend on whether the route of administration is systemic or intracerebral. Using 50-day-old male rats, we compared the effects of IL-1b on brain γ-glutamyl transpeptidase (GGT; an enzymatic marker of brain capillary endothelium) at 2, 24 and 96 h after either an intravenous (i.v.) injection of 5 μg IL-1β or an intracerebroventricular (i.c.v. - lateral ventricle) infusion of 50 ng IL-1β. When the i.v. route was used, the GGT activity underwent small but significant changes; decreasing in the hippocampus 2 h after the i.v. injection, increasing 24 h later and returning to control levels at 96 h. No significant changes in the hippocampal GGT activity were observed at 2 and 24 h following the i.c.v. infusion. The GGT activity in the hypothalamus remained unchanged regardless of the route of IL-1b administrations. Similar changes in GGT activity were revealed histochemically. The labeling was found mainly in the capillary bed, the changes being most evident in the hippocampal stratum radiatum and stratum lacunosum-moleculare. A transient increase in GGT activity at 24 h, together with a less sharp delineation of GGT-stained vessels, may reflect IL-1b induced increased turnover of glutathione and/or oxidative stress, that may in turn, be related to altered permeability of the blood-brain barrier in some neurological and mental disorders, including schizophrenia.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
26785. The influence of land abandonment on farmland bird communities: a case study from a floodplain landscape in Continental Croatia
- Creator:
- Radović, Andreja, Nikolov, Stoyan C., Tepić, Nataša, Mikulić, Krešimir, Jelaska, Sven D., and Budinski, Ivan
- Type:
- article, model:article, and TEXT
- Subject:
- agriculture, Amorpha fruticosa, invasion, and management
- Language:
- English
- Description:
- The abandonment of less productive agricultural land and the intensification of agricultural land use are the main features of the Common Agricultural Policy (CAP) that Croatia will enforce now as new member of the EU. Due to demographic changes and the economic transition in Croatia resulting from war in the 1990s, substantial tracts of agricultural land were abandoned. We investigated two habitat types in the protected floodplain landscape of Lonjsko polje in the continental part of the country: arable land and pastures. Both habitats were maintained by agricultural management and suffered from partial abandonment. Land abandonment increased the susceptibility to encroachment by the invasive plant species Amorpha fruticosa. Data on bird communities were obtained during the breeding season in 2010 while there were high water levels in the floodplain. Data were collected from 63 points, and a total of 1447 individuals from 70 species were recorded during the study. We found that the bird community structure was primarily related to the presence/abandonment of agricultural land use and the habitat type. Further, we detected that the bird community structure in the same habitat type differed by management intensity. Open habitat specialists were most influenced by land abandonment. However, the conservation value (according to the Species of European Conservation Concern value, SPEC) of grazed pastures and abandoned pastures did not differ significantly, in part because the overgrown pastures with high water levels were found to be suitable for Acrocephalus species. The shift in bird community structure between abandoned and managed arable lands were smaller than those detected in the pastoral communities. Because land abandonment is a widespread phenomenon in Croatia, we emphasize the urgent need for a nationwide monitoring program for farmland birds to register the resulting changes in farmland bird communities and to develop appropriate agri-environment measures to mitigate the process.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
26786. The influence of low-frequency left prefrontal repetitive transcranial magnetic stimulation on memory for words but not faces
- Creator:
- Škrdlantová, L., Horáček, J., Dockery, C., Lukavský, J., Kopeček, M., Preiss, M., Novák, T., and Höschl, C.
- Type:
- article, model:article, and TEXT
- Subject:
- Face memory, Verbal memory, Repetitive transcranial magnetic stimulation, and rTMS
- Language:
- English
- Description:
- Brain imaging studies suggest localization of verbal working memory in the left dorsolateral prefrontal cortex (DLPFC) while face processing and memory is localized in the inferior temporal cortex and other brain areas. The goal of this study was to assess the effect of left DLPFC low-frequency repetitive transcranial magnetic stimulation (rTMS) on verbal recall and face recognition. The study revealed a significant decrease of free recall in word encoding under rTMS (110 % of motor threshold, 0.9 Hz) in comparison with sham stimulation (p=0.03), while no significant difference was found with facial memory tests. Our findings support the essential role of the left DLPFC in word but not facial memory and confirm the content specific arrangement of cortical areas involved in semantic memory. As a non-invasive tool, rTMS is useful for cognitive brain mapping and the functional localization of the category specific memory system.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
26787. The influence of monovalent cations on trimeric G protein Gi1α activity in HEK293 cells stably expressing DOR-Gi1α (Cys351-Ile351) fusion protein
- Creator:
- Vošahlíková, M. and Petr Svoboda
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, δ-opioid receptor (DOR), monovalent ions, Gi1α protein, 14, and 612
- Language:
- English
- Description:
- The effect of monovalent cations on trimeric G protein Gi1α was measured at equimolar concentration of chloride anion in pertussis-toxin (PTX)-treated HEK293 cells stably expressing PTX- insensitive DOR-Gi1α (Cys351-Ile351) fusion protein by high-affinity [35S]GTPγS binding assay. The high basal level of binding was detected in absence of DOR ag onist and monovalent ions and this high level was inhibited with the order of: Na+>K+>Li+. The first significant inhibition was detected at 1 mM NaCl. The inhibition by monovalent ions was reversed by increasing concentrations of DOR agonist DADLE. The maximum DADLE response was also highest for sodium and decreased in the order of: Na+>K+≈Li+. Our data indicate i) an inherently high activity of trimeric G protein G i 1 α when expressed within DOR-Gi1α fusion protein and determined in the absence of monovalent cations, ii) preferential sensitivity of DOR-Gi1α to sodium as far as maximum of agonist response is involved., M. Vošahlíková, P. Svoboda., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
26788. The influence of n-3 polyunsaturated fatty acids and very low calorie diet (VLCD) during a short-term weight reducing regimen on weight loss and serum fatty acid composition in severely obese women
- Creator:
- Kunešová, M., Braunerová, R., Hlavatý, P., Tvrzická, E., Staňková, B., Škrha, J., Hilgertová, J., Hill, M., Kopecký, J., Wagenknecht, M., Hainer, V., Matoulek, M., Pařízková, J., Žák, A., and Svačina, Š.
- Type:
- article, model:article, and TEXT
- Subject:
- Obesity treatment, Fatty acid composition, very low calorie diet, Beta-hydroxybutyrate, and PUFA
- Language:
- English
- Description:
- Polyunsaturated fatty acids of n-3 series (n-3 PUFA) were shown to increase basal fat oxidation in humans. The aim of the study was to compare the effect of n-3 PUFA added to a very low calorie diet (VLCD), with VLCD only during three-week inpatient weight reduction. Twenty severely obese women were randomly assigned to VLCD with n-3 PUFA or with placebo. Fatty acids in serum lipid fractions were quantified by gas chromatography. Differences between the groups were determined using ANOVA. Higher weight (7.55±1.77 vs. 6.07±2.16 kg, NS), BMI (2.82± 0.62 vs. 2.22±0.74, p<0.05) and hip circumference losses (4.8±1.81 vs. 2.5±2.51cm, p<0.05) were found in the n-3 group as compared to the control group. Significantly higher increase in beta-hydroxybutyrate was found in the n-3 group showing higher ketogenesis and possible higher fatty acid oxidation. The increase in beta-hydroxybutyrate significantly correlated with the increase in serum phospholipid arachidonic acid (20:4n-6; r = 0.91, p<0.001). In the n-3 group significantly higher increase was found in n-3 PUFA (eicosapentaenoic acid, 20:5n-3, docosahexaenoic acid, 22:6n-3) in trigycerides and phospholipids. The significant decrease of palmitoleic acid (16:1n-7) and vaccenic acid (18:1n-7) in triglycerides probably reflected lower lipogenesis. A significant negative correlation between BMI change and phospholipid docosahexaenoic acid change was found (r = -0.595, p<0.008). The results suggest that long chain n-3 PUFA enhance weight loss in obese females treated by VLCD. Docosahexaenoate (22:6n-3) seems to be the active component.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
26789. The influence of nitric oxide synthase inhibitor L-NAME on bones of male rats with streptozotocin-induced diabetes
- Creator:
- Petr Broulík, Martin Haluzík, and Jan Škrha
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, osteoklasty, osteoclasts, streptozotocin diabetes, osteopenia, L-NAME, TRAP, 14, and 612
- Language:
- English
- Description:
- The pathophysiological processes underlying the development of diabetic osteopenia has not hitherto been elucidated. Induction of streptozotocin diabetes leads in our experiments to decrease of bone density, ash, mineral content and to thinner cortical width compared to control male rats. In order to investigate the pathogenetic role of bone resorption by osteoclasts in streptozotocin-induced diabetes, we determined the circulating levels of tartrate-resistant acid phosphatase (TRAP), a biochemical marker for bone resorption. Plasma TRAP values in diabetic rats did not differ from their corresponding controls. Streptozotocin diabetes by itself did not have any effect on the weight of seminal vesicles which are highly testosterone-dependent. Low doses of nitric oxide cause bone resorption, but higher doses of NO inhibit bone resorbing activity. We examined the effect of L-NAME (inhibitor of nitric oxide production) after six weeks of administration to diabetic rats. There was no further significant loss of bone mineral density, ash and mineral content or tibia weight in diabetic rats treated with L-NAME. L-NAME itself did not decrease bone metabolism. In our study no evidence of an increased bone resorption was found. Our results have indicated that a predominance of bone resorption over bone formation is not involved in the pathogenesis of diabetes-associated osteopenia. Inhibition of NO neither increased osteoclastic activity (TRAP) nor induced osteopenia in L-NAME-treated rats. This suggests a possibility that NO is not involved in the pathogenesis of diabetic osteopenia., P. D. Broulík, M. Haluzík, J. Škrha., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
26790. The influence of NO synthase inhibitor and free oxygen radicals scavenger - methylene Bblue - on streptozotocin induced diabetes in rats
- Creator:
- Haluzík, M., Nedvídková, J., and Škrha, J.
- Type:
- article, model:article, and TEXT
- Subject:
- diabetes, rat, oxidative stress, nitric oxide, superoxide dismutase, and malondialdehyde
- Language:
- English
- Description:
- The excessive production of nitric oxide (NO) and the subsequent increase of local oxidative stress is suggested as one of the pathophysiological mechanisms of streptozotocin-induced diabetes. It was reported that the administration of NO synthase inhibitors partially attenuated the development of streptozotocin-induced diabetes and reduced hyperglycaemia. Here we have studied the influence of methylene blue, which combines the properties of NO synthase inhibitor with antioxidant effects. The experiments were performed on male rats divided into four groups: control, diabetic (single dose of 70 mg of streptozotocin/kg i.p.), methylene blue (50 mg/kg in the food) and diabetic simultaneously fed with methylene blue. After 45 days the experiments were discontinued by decapitation. Serum glycaemia, glycated haemoglobin and oxidative stress parameters (plasma malondialdehyde concentration and erythrocyte superoxide dismutase activity) were significantly higher in the diabetic group. Simultaneous methylene blue administration partially reduced glycaemia and glycated haemoglobin, but did not decrease oxidative stress. We conclude that NO synthase inhibitor methylene blue partially attenuates the development of streptozotocin-induced diabetes in male rats, but does not reduce the development of oxidative stress in the diabetic group.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public